Plug-in coupling for medical apparatus



FIG. 1 is a side elevational view of a plug-in coupling for medical apparatus in accordance with my design;

FIG. 2 is a front elevational view thereof;

FIG. 3 is a top, front, right perspective view thereof; and,

FIG. 4 is a top, front, left perspective view thereof.

The broken lines in the drawings show unclaimed environment only and form no part of the claimed design. 

CLAIM The ornamental design for a plug-in coupling for medical apparatus, as shown and described. 